Hi ALAN
I had the same problem recently I when to my local repair shop.
Should cost no more than £50 for a new line output transformer + installation
if you also need a new geometry board, make sure you ask the shop to recalibrate the TV after installation mine forgot and I had to do my self.
If after installation you get a funny looking picture e.g. stretched or skewed then,    
on the front panel  press and hold Vol down & CH up and power on form standby to access the service menu use up and down CH to navigate and vol down and up to change settings.
MAKE SURE YOU WRITE DOWN THE ORIGINAL SETTINGS
AND NEVER CHANGE THE D.V.C.O SETTING
                
 Daniel Vose
                
 November 2006